JP3517606B2 - motor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultra-compact cylindrical motor.

[0002]

2. Description of the Related Art A conventional small cylindrical step motor is shown in FIG. A stator coil 105 is concentrically wound around the bobbin 101, and the bobbin 101 is sandwiched and fixed by two stator yokes 106 in the axial direction. 106 a and 106 b are alternately arranged, and a stator yoke 106 integral with the stator teeth 106 a or 106 b is fixed to the case 103 to form a stator 102.

A flange 115 is provided on the two sets of cases 103.
The bearing 108 is fixed, and another bearing 108 is fixed to the other case 103. The rotor 109 is composed of a rotor magnet 111 fixed to a rotor shaft 110, and the rotor magnet 111 is the stator yoke 10 of the stator 102.
6a and radial gaps are formed. The rotor shaft 110 is rotatably supported between the two bearings 108.

[0004]

However, the above-mentioned conventional small step motor has the case 10 on the outer circumference of the rotor.
3, the bobbin 101, the stator coil 105, and the stator yoke 106 are arranged concentrically, so that there is a drawback that the outer dimension of the motor becomes large. Further, as shown in FIG. 7, the magnetic flux generated by energizing the stator coil 105 is mainly the end surface 106a1 of the stator tooth 106a.
And the end faces 106b1 of the stator teeth 106b are not passed, so that the rotor magnet 111 is not effectively acted, so that the output of the motor does not increase.

The present applicant has proposed a motor that solves such a problem in Japanese Patent Application Laid-Open No. 09-331666. The proposed motor has a cylindrical rotor having permanent magnets that are equally divided in the circumferential direction and are alternately magnetized to different poles. The first coil, the rotor, and the second rotor are axially formed in the rotor.
Are sequentially arranged, the first outer magnetic pole and the first inner magnetic pole excited by the first coil are opposed to the outer peripheral surface and the inner peripheral surface of the rotor, and the second magnetic pole is excited by the second coil. The outer magnetic pole and the second inner magnetic pole are configured to be opposed to the outer peripheral surface and the inner peripheral surface of the rotor, and the rotating shaft that is the rotor shaft is taken out from the cylindrical permanent magnet.

The motor having such a structure can have a high output and a small outer size. However, by further thinning the magnet in the above structure, the first outer magnetic pole and the first inner magnetic pole are separated. If the distance between them and the distance between the second outer magnetic pole and the second inner magnetic pole can be reduced, the magnetic resistance of the magnetic circuit can be reduced. According to this, a large amount of magnetic flux can be generated with a small current flowing through the first coil and the second coil.

In order to facilitate the assembling of the above-mentioned motor, the applicant of the present invention has disclosed in Japanese Patent Laid-Open No. 10-215558 that a cylindrical shape is formed and at least the outer peripheral surface is divided in the circumferential direction and alternately attached to different poles. A magnet,
A first bobbin around which the coil is wound, a second bobbin around which the coil is wound, and a first bobbin facing the outer peripheral surface of the magnet excited by the coil wound around the first bobbin. An outer magnetic pole portion, a first inner magnetic pole portion that faces the inner peripheral surface of the magnet, and a second outer magnetic pole portion that is excited by a coil wound around the second bobbin and faces the outer peripheral surface of the magnet. A second inner magnetic pole portion facing the inner peripheral surface of the magnet, the first outer magnetic pole portion and the second outer magnetic pole portion.
Has proposed a motor provided with a coupling member which holds the outer magnetic pole portions concentrically and which is made of a material having a spring property and has a slit formed on a circumferential surface in a direction parallel to the axis.

However, there is a risk that dust may enter the motor through the slit and cause malfunction.

Further, in order to facilitate the assembling of the above-mentioned motor, the applicant of the present invention has disclosed in Japanese Patent Laid-Open No. 10-215558 that a cylindrical shape is formed and at least the outer peripheral surface is divided in the circumferential direction and alternately attached to different poles. A magnet,
A first bobbin having a bobbin terminal portion to which a terminal pin having a coil wound and electrically connected at both ends is fixed; and a terminal pin having a coil wound and both ends electrically connected to the bobbin. A second bobbin having a fixed bobbin terminal portion, a first outer magnetic pole portion that is excited by a coil wound around the first bobbin and faces the outer peripheral surface of the magnet, and an inner peripheral surface of the magnet. A first inner magnetic pole portion facing the surface, a second outer magnetic pole portion facing the outer peripheral surface of the magnet and excited by a coil wound around the second bobbin, and an inner peripheral surface of the magnet. There is proposed a motor including a second inner magnetic pole portion facing each other and a connecting member that holds the first outer magnetic pole portion and the second outer magnetic pole portion concentrically.

The configuration diagram is shown in FIGS. 7 is an external view of the motor, FIG. 8 is a perspective view of the bobbin, and FIG. 9 is a sectional view of the bobbin. 201 is a first outer magnetic pole portion, 202 is a second outer magnetic pole portion, 203 is a connecting member, 2
05 is a coil, 204 and 208 are bobbins, and 207 and 20
8, 209 and 210 are terminal portions 2 of the bobbins 204 and 208.
Both ends of the coil fixed to the portions 04a and 208a are terminal pins soldered. Bobbin 2 for bobbin 208
A coil (not shown) is wound in the same manner as 04.

However, since the bobbin terminal portion of the bobbin, particularly the portion A in FIG. 9, has a thin shape and weak mechanical strength, it has a drawback that it will be destroyed if an external force is applied carelessly.

Accordingly, an object of the present invention is to provide a hard easy high and assembling a small output dust is mixed motor. Furthermore, the bobbin terminal part is destroyed
It is to provide a motor that is difficult to do.

[0013]

In order to achieve the above object, a motor according to the present invention has an outer peripheral surface divided in the circumferential direction.
And magnets that are alternately magnetized to different poles
The magnet is placed in the axial direction of the
The first coil and the second coil, and the first coil
A wound first bobbin and a second wound second coil
Of the first bobbin and the outer peripheral surface of one end of the magnet.
A first outer magnetic pole excited by the coil and a magnet
Magnetized by the first coil facing the inner surface of one end of the
The first inner magnetic pole and the outer peripheral surface of the other end of the magnet.
A second outer magnetic pole that is excited by the second coil
And a second coil facing the inner surface of the other end of the magnet.
Therefore, it is possible to use a non-magnetic material and a second inner magnetic pole that is excited.
A first outer magnetic pole and a second outer pole which are made of a flexible material.
A connecting member for fixing the outer magnetic pole portion of the
The first bobbin has a slit for facilitating the deformation.
And a second bobbin covers the slit
It

[0014]

Connecting member made of flexible material
Has a slit, the first outer magnetic pole portion and the second
The outer magnetic pole portion can be held without play . That
Because, it becomes easy to assemble the motor with well with the first outer magnetic pole portion concentricity rectification <br/> of the second outer magnetic pole portion.

Furthermore, it is possible to prevent the slit because some ball bin is configured to cover the outer periphery of the slit of the connecting member contamination of dust into the interior of the motor with a simple configuration.

[0017]

[0018]

[0019]

[0020]

[0021]

In order to achieve the above object, the above
The motor has a first bobbin and the second bobbin engaged with each other.
It is characterized by Since the bobbin terminals are engaged with each other, the strength is increased and damage due to careless external force is prevented.

[0023]

1 to 4 are views showing a step motor according to a first embodiment of the present invention, in which FIG. 1 is an exploded perspective view of the step motor, and FIG. 2 is an axial direction after the step motor is assembled. 3 is a sectional view taken along the line AA and a sectional view taken along the line BB in FIG. 2. FIG. 4 is an external view of the step motor.

1 to 4, reference numeral 1 denotes a cylindrical magnet constituting a rotor, and the magnet 1 which is the rotor has its outer peripheral surface divided into n in the circumferential direction (in the present embodiment, 10 divisions). Magnetized portions 1a, 1b, 1c, 1d, 1e, 1f, 1g in which the S pole and the N pole are alternately magnetized.
1h, 1i, 1j, the magnetized portions 1a, 1c, 1
e, 1g, 1i are magnetized to the S pole, and the magnetized portions 1b, 1d,
1f, 1h, and 1j are magnetized to the N pole. The magnet 1 is made of a plastic magnet material formed by injection molding. Thereby, the thickness of the cylindrical shape in the radial direction can be made very thin.

Further, the magnet 1 is provided with a fitting portion 1w having a small inner diameter at the central portion in the axial direction. An output shaft 10 serves as a rotor shaft, and the output shaft 10 is press-fitted and fixed to a fitting portion 1w of the magnet 1 serving as a rotor. Since the magnet 1 is made of a plastic magnet molded by injection molding, cracks do not occur even when assembled by press fitting, and it is easy to manufacture even a complicated shape having a fitting portion 1w with a small inner diameter in the axial center part. Become. Further, since the output shaft 10 and the magnet 1 are assembled and fixed by press fitting, the assembly is easy and the manufacturing can be performed at a low cost. The output shaft 10 and the magnet 1 constitute a rotor.

In particular, Nd-Fe is used as the material of the magnet 1.
A plastic magnet formed by injection molding a mixture of a B-based rare earth magnetic powder and a thermoplastic resin binder material such as polyamide is used. As a result, the bending strength of the compression-molded magnet is about 500 Kgf / cm ² , whereas, for example, when polyamide resin is used as the binder member,
A bending strength of 0 Kgf / cm ² or more is obtained, and a thin-walled cylindrical shape, which cannot be obtained by compression molding, can be formed. The thin cylindrical shape enhances the performance of the motor as described later.

Further, the shape can be freely set, the shape for fixing the rotor shaft, which cannot be obtained by compression molding, can be integrated, and sufficient rotor shaft fixing strength can be obtained. Further, since it has excellent strength, it will not crack even if a method such as press fitting the rotor shaft is used.

At the same time, since the rotor shaft fixing portion is integrally formed, the coaxial accuracy of the magnet portion with respect to the rotor shaft portion is improved, and it is possible to reduce the runout, thereby reducing the gap distance between the magnet and the stator portion. Is possible, and the magnetic characteristics of the compression magnet are 8MGO.
While the magnetic characteristics of the injection-molded magnet are about 5 to 7 MGOe, the sufficient output torque of the motor can be obtained. In addition, there is no adhesion of magnetic powder, which is a problem with compression magnets, and there is no bulging of the surface that tends to occur during rust-preventive coating, and quality can be improved.

2 and 3 are first and second bobbins, 4 is a cylindrical first coil wound around the bobbin 2, and 5 is a cylindrical bobbin wound around the bobbin 3. Second
Of the coil. First coil 4 and second coil 5
Are arranged concentrically with the magnet 1 and at positions sandwiching the magnet 1 in the axial direction, and the outer diameters of the first coil 4 and the second coil 5 are substantially the same as the outer diameter of the magnet 1.

The first bobbin 2 and the second bobbin 3 are formed with bobbin terminal portions 2a and 3a. Terminal pins 6 and 7 made of a metal material are fixed to the terminal portion 2a of the first bobbin 2, and the first coil 4 is attached to the terminal pins 6 and 7.
Both ends of are electrically connected by soldering or the like.
Terminal pins 8 and 9 made of a metal material are fixed to the terminal portion 3a of the second bobbin 3, and both ends of the first coil 4 are electrically connected to the terminal pins 8 and 9 by soldering or the like. Has been done. A protrusion 2b is further formed on the terminal portion 2a of the first bobbin 2, and a pin 2c and a hole 2d are formed at the tip of the protrusion 2b. A projection 3b is further formed on the terminal portion 3a of the second bobbin 3, and a pin 3c and a hole 3d are formed at the tip of the projection 3b. The pin 2c of the first bobbin 2 has a hole 3d of the second bobbin 3,
The hole 2d of the first bobbin 2 engages with the pin 3c of the second bobbin 3 in a press-fitted state in the assembled state of the motor,
In the first bobbin 2 and the second bobbin 3, the bobbin terminal portions 2a and 3a are fixed to each other to increase mechanical strength, and an accident such that the bobbin terminal portion is broken by an unexpected external force may occur. Can be prevented.

The pin 2c of the first bobbin 2 has a hole 3d of the second bobbin 3, and the hole 2d of the first bobbin 2 has a pin 3c of the second bobbin 3 as an engaging portion.

Reference numerals 18 and 19 are the first made of a soft magnetic material.
Of the first stator and the second stator, the phase of the first stator and the second stator is 180 / n degrees, that is, 18 °.
The first stator and the second stator, which are arranged offset from each other, include an outer cylinder and an inner cylinder. The outer cylinder of the first stator 18 has a tip portion that is the first outer magnetic pole 18a,
18b, 18c, 18d and 18e are formed.

Reference numeral 21 denotes a first auxiliary stator, which has an inner diameter portion 21f.
Is fitted and fixed to the inner cylinder 18f of the first stator 18, and the outer magnetic pole 18a of the first stator is attached to the outer diameter portion.
18 b, 18 c, 18 d, 18 e
21a, 21b, 21c, 21d, 2 which are the inner magnetic poles of
The 1e portion is formed. First inner magnetic poles 21a, 21
The portions b, 21c, 21d, and 21e are 360 / (n / n) so that they have the same phase with respect to the magnetization of the magnet 1.
2) Deviated from each other, that is, 72 °. The outer cylinder of the second stator 19 has a second outer magnetic pole 19a at its tip.
19b, 19c, 19d and 19e are formed.

A second auxiliary stator 22 has an inner diameter portion 22f.
Of the second stator 19 are fitted and fixed to the inner cylinder 19f, and the outer magnetic pole 19 of the second stator is attached to the outer diameter portion.
22a, 22b, 22c, 22 serving as second inner magnetic poles in phases facing a, 19b, 19c, 19d, 19e.
The d and 22e parts are formed. Second inner magnetic pole 22
The portions a, 22b, 22c, 22d, and 22e are set to have the same phase with respect to the magnetization of the magnet 1 in 360 /
The second outer magnetic poles 19a and 19b of the second stator 19 are formed with a deviation of (n / 2) degrees, that is, 72 degrees.
19c, 19d, and 19e are 360 / (n / 2) degrees so that they have the same phase with respect to the magnetization of the magnet 1.
That is, they are formed with a deviation of 72 degrees.

Outer magnetic poles 18a, 1 of the first stator 18
8b, 18c, 18d, 18e and the second stator 19
The outer magnetic poles 19a, 19b, 19c, 19d, and 19e are each formed of a notch hole and teeth extending in a direction parallel to the axis. With this configuration, it is possible to form the magnetic pole while minimizing the diameter of the motor. In other words, if the outer magnetic pole is formed by the unevenness extending in the radial direction, the diameter of the motor is increased accordingly, but in the present embodiment, the outer magnetic pole is formed by the notch hole and the teeth extending in the direction parallel to the axis. Since it is configured, the diameter of the motor can be minimized.

Outer magnetic poles 18a, 1 of the first stator 18
8b, 18c, 18d, 18e and the outer diameter portions 21a, 21b, 21 of the first auxiliary stator serving as the first inner magnetic poles.
The c, 21d, and 21e are provided so as to face the outer peripheral surface and the inner peripheral surface on one end side of the magnet 1 and to sandwich the one end side of the magnet 1. Also, the hole 18f of the first stator 18
The output shaft 10 has one end rotatably fitted therein.

Outer magnetic poles 19a, 1 of the second stator 19
9b, 19c, 19d, 19e and the outer diameter portions 22a, 22b, 22 of the second auxiliary stator serving as the second inner magnetic poles.
c, 22d, and 22e are provided so as to sandwich the other end of the magnet 1 so as to face the outer peripheral surface and the inner peripheral surface of the other end of the magnet 1. Also, the hole 19f of the second stator 19
The other end of the output shaft 10 is rotatably fitted in the shaft.

The coil 2 is provided between the outer cylinder and the inner cylinder of the first stator 18, and the first stator 18 and the first auxiliary yoke 21 are energized by energizing the coil 2.
And are excited.

The coil 3 is provided between the outer cylinder and the inner cylinder of the second stator 19, and the second stator 19 and the second auxiliary yoke 22 are energized by energizing the coil 3.
And are excited.

Therefore, the magnetic flux generated by the coil 2 is the outer magnetic poles 18a, 18b, 18c, 18d, 18e and the inner magnetic poles 21a, 21b, 21c, 21d, 21e.
Since it crosses the magnet 1 which is the rotor between
The magnetic flux which effectively acts on the magnet as the rotor and is generated by the coil 3 causes the outer magnetic poles 19a, 19b, 19c,
19d, 19e and inner magnetic poles 22a, 22b, 22
Since it crosses the magnet 1 which is a rotor between c, 22d and 22e, it effectively acts on the magnet which is a rotor to increase the output of the motor.

Further, the magnet 1 is made of the plastic magnet material formed by injection molding as described above, so that the thickness of the cylindrical shape in the radial direction can be made very thin. Therefore, the distance between the outer magnetic poles 18a, 18b and the inner magnetic poles 18c, 18d of the first stator 18 can be made very small, and the magnetic resistance of the magnetic circuit formed by the coil 2 and the first stator can be made small. Similarly, the distance between the outer magnetic poles 19a, 19b and the inner magnetic poles 19c, 19d of the second stator 19 can be made very small, and the magnetic resistance of the magnetic circuit formed by the coil 3 and the second stator can be made small. As a result, a large amount of magnetic flux can be generated with a small amount of current, so that the output of the motor can be increased, the power consumption can be reduced, and the size of the coil can be reduced.

The gate of the magnet 1 during injection molding does not face the outer magnetic poles 18a, 18b of the first stator 18 and the outer magnetic poles 19a, 19b of the second stator 19 and their outer magnetic poles 18a, 18b, 19a. , 19b. The gate is indicated by G in FIG. By setting this position, the motor output characteristics will not be affected even if magnetic imbalance or surface irregularities occur due to post-processing such as remaining gate after molding or removal of remaining gate, so that a good motor is created. be able to.

Reference numeral 20 denotes a connecting ring which is made of a non-magnetic material and a flexible material such as stainless steel for springs and phosphor bronze for springs and which is a substantially cylindrical member having slits 20b formed therein. The slit 20b is formed on the circumferential surface in a direction parallel to the axial direction.

The connecting ring 20 as a single unit has an inner diameter portion 20.
The diameter of a is set to be smaller than the outer diameter of the outer magnetic poles of the first stator 18 and the second stator 19, and the diameter of the inner diameter portion 20a is set to the first stator 18 and the second stator 1.
When the outer magnetic pole portion 9 is inserted, the coupling ring 20 elastically deforms and elastically holds the first stator and the second stator 19. At this time, the first stator 18 and the second stator 19 are fixed in a state in which the phases are shifted by 180 / n degrees, that is, 18 degrees, and the tips are separated by a certain distance.

That is, the outer magnetic pole 18 of the first stator 18
a, 18b, 18c, 18d, 18e and the outer magnetic poles 19a, 19b, 19c, 19 of the second stator 19.
The tips of d and 19e are arranged so as to face each other with a certain distance in the direction parallel to the axis and a phase shift of 180 / n degrees, that is, 18 degrees with respect to the position in the rotational direction.

Since the connecting ring is made of a non-magnetic material, the first stator 18 and the second stator 19 can be separated from each other on the magnetic circuit so that they do not affect each other and the motor performance is stabilized.

The slit 20b of the connecting ring 20 is provided so that the connecting ring 20 can be deformed relatively easily. According to this structure, the first stator 18 and the second stator 1
9 has a structure free from play during assembly, and the first stator 18 and the second stator 19 are assembled with the concentricity secured with high accuracy. After that, the connecting ring 20, the first stator 18, and the second stator 19 are fixed by welding or adhesion. Due to the slits 20b, dust is mixed in from the slits 20b and adheres to the magnet 1 to easily cause a malfunction.

In this embodiment, a part of the bobbin, that is, the protrusion 2b provided with the bobbin terminal portion 2a of the first bobbin 2 and the second bobbin
Bobbin 3 of the bobbin 3 of the projection 3b provided with the terminal portion 3a
Thus, the slit 20b is closed because it is configured to cover the outer peripheral surface of the slit 20b of the coupling ring 20. This makes it possible to prevent dust from entering from the outside.

FIG. 2 is a sectional view of the step motor, and FIGS. 3 (a), (b), (c) and (d) are sectional views taken along the line AA of FIG. ), (F), (g), (h)
Shows a sectional view taken along the line BB of FIG. Figure 3 (a)
And (e) are cross-sectional views at the same point, FIGS. 3 (b) and (f) are cross-sectional views at the same point, and FIGS. 3 (c) and (g).
3A and 3B are cross-sectional views of the simultaneous points, and FIGS. 3D and 3H are cross-sectional views of the simultaneous points.

Next, the operation of the step motor will be described. From the state of FIGS. 3A and 3E, the coils 2 and 3 are energized so that the outer magnetic poles 18a, 18b, 1 of the first stator 18 are
8c, 18d, and 18e are N poles, and the first auxiliary yoke 2
First inner magnetic poles 21a, 21b, 21c, 2 made of 1
1d and 21e are S poles, the outer magnetic poles 19a, 19b, 19c, 19d and 19e of the second stator 19 are N poles, and the second inner magnetic pole 22 is composed of the second auxiliary yoke 22.
When a, 22b, 22c, 22d, and 22e are excited to the S pole, the magnet 1 that is the rotor rotates counterclockwise by 18 degrees, and the states shown in FIGS. 3B and 3F are obtained.

Next, the energization of the coil 2 is reversed, and the outer magnetic poles 18a, 18b, 18c, 18 of the first stator 18 are reversed.
d and 18e are S poles, and the first inner magnetic poles 21a, 21b, 21c, 21d and 21 formed of the first auxiliary yoke 21.
e is the N pole, and the outer magnetic pole 19a of the second stator 19 is
19b, 19c, 19d and 19e are N poles, and second inner magnetic poles 22a and 22b are formed of a second auxiliary yoke 22.
When 22c, 22d, and 22e are excited to the S pole, the magnet 1 that is the rotor further rotates counterclockwise by 18 degrees,
The state shown in FIGS. 3C and 3G is obtained.

Next, the energization of the coil 3 is reversed and the outer magnetic poles 18a, 18b, 18c, 18 of the first stator 18 are reversed.
d and 18e are S poles, and the first inner magnetic poles 21a, 21b, 21c, 21d and 21 formed of the first auxiliary yoke 21.
e is the N pole, and the outer magnetic pole 19a of the second stator 19 is
19b, 19c, 19d and 19e are S poles, and second inner magnetic poles 22a and 22b are formed of a second auxiliary yoke 22.
When 22c, 22d, and 22e are excited to the N pole, the magnet 1 as the rotor further rotates counterclockwise by 18 degrees,
The state shown in FIGS. 3D and 3H is obtained.

Thereafter, by sequentially switching the energizing directions to the coils 2 and 3 in this manner, the magnet 1 as a rotor is rotated to a position corresponding to the energizing phase.

Here, it will be described that the stepping motor having such a structure is an optimum structure for making the motor extremely small. The basic structure of the step motor will be described. First, the magnet is formed in a hollow cylindrical shape, and secondly, the outer peripheral surface of the magnet is divided into n in the circumferential direction and alternately magnetized to different poles. Thirdly, the first coil, the magnet, and the second coil are arranged in this order in the axial direction of the magnet, and fourthly, the first and second stators excited by the first and second coils. The outer magnetic pole and the inner magnetic pole are opposed to the outer peripheral surface and the inner peripheral surface of the magnet. Fifth, the outer magnetic pole is composed of a notch hole and a tooth extending in a direction parallel to the axis. .

The diameter of the step motor may be large enough to allow the stator poles to face the diameter of the magnet, and the length of the step motor is the same as the length of the magnet between the first coil and the second coil. It would be good if the length was just added. Therefore, the size of the step motor is determined by the diameter and the length of the magnet and the coil, and if the diameter and the length of the magnet and the coil are made extremely small, the step motor can be miniaturized. .

At this time, if the diameter and the length of the magnet and the coil are made extremely small, it becomes difficult to maintain the accuracy as a step motor. This is because the first and second outer surfaces and the inner surface of the magnet are the same. The problem of the accuracy of the step motor is solved by a simple structure in which the outer magnetic pole and the inner magnetic pole of the stator are opposed to each other. At this time, if not only the outer peripheral surface of the magnet but also the inner peripheral surface of the magnet is divided in the circumferential direction and magnetized, the output of the motor can be further increased.

FIG. 4 is an external view of this motor. Thus, the slit 20b of the connecting member 20 is completely covered by a part of the bobbin.

[0058]

As described above in detail, according to the present invention, the slit having the flexible material is provided.
The first outer magnetic pole portion and the second outer magnetic pole portion are connected by the connecting member.
Can be held without play, the first outer magnetic pole portion and the second outer magnetic pole portion
Assemble the motor by improving the accuracy of concentricity of the outer magnetic pole.
It will be easy. In addition, part of the bobbin is the connecting member
Since it is configured to cover the outer periphery of the rit, the slit
To prevent dust from entering the inside of the motor with a simple structure.
You can

[0059]

[0060]

[0061]

Further , the first bobbin and the second bobbin are associated with each other.
By combining them, the bobbin terminals are engaged with each other, so that the strength is increased and the destruction due to the careless external force is prevented.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a step motor according to a first embodiment of the present invention.

FIG. 2 is a sectional view of the step motor shown in FIG. 1 in a completed assembled state.

FIG. 3 is an explanatory diagram of a rotation operation of a rotor of the step motor shown in FIG.

FIG. 4 is an external view of a step motor.

FIG. 5 is a sectional view of a conventional step motor.

FIG. 6 is a sectional view showing a state of a stator of a conventional step motor.

FIG. 7 is an external view of a conventional step motor.

FIG. 8 is a perspective view of a bobbin of a conventional step motor.

FIG. 9 is a sectional view of a bobbin of a conventional step motor.

[Explanation of symbols]

1 magnet 2 first bobbin 2a terminal portion 2b protrusion 2c pin 2d hole 3 second bobbin 3a terminal portion 3b protrusion 3c pin 3d hole 4 first coil 5 second coil 6, 7, 8, 9, Terminal pin 6, 7 10 Output shaft 18 First stator 18a, 18b, 18c, 18d, 18e First outer magnetic pole 19 Second stator 19a, 19b, 19c, 19d, 19e Second outer magnetic pole 20 Coupling ring 20b Slit 21 First auxiliary yoke 22 Second auxiliary yoke

Claims (2)

(57) [Claims] 1. A magnet having an outer peripheral surface divided in the circumferential direction and magnetized to have different poles alternately, a first coil and a second coil arranged at a position sandwiching the magnet in the axial direction of the magnet. Coil, a first bobbin around which the first coil is wound, a second bobbin around which the second coil is wound, and a first bobbin that faces the outer peripheral surface of one end of the magnet. A first outer magnetic pole that is excited by the first inner magnetic pole that opposes the inner peripheral surface of one end of the magnet, and a first inner magnetic pole that is excited by the first coil that opposes the outer peripheral surface of the other end of the magnet. A second outer magnetic pole excited by the second coil, a second inner magnetic pole opposed to the inner peripheral surface of the other end of the magnet and excited by the second coil, and a non-magnetic material and Made of flexible material A connecting member that fixes the first outer magnetic pole and the second outer magnetic pole portion, the connecting member has a slit for facilitating deformation, and the first bobbin and the A motor characterized in that a second bobbin covers the slit. 2. The motor according to claim 1, wherein the first bobbin and the second bobbin are engaged with each other.